Photographic machine



Nov. 18, 1941.

A. COLEMAN PHOTOGRAPHIC HACHINE Filed June 15, 1939 3 Sheets-Sheet 1 r.Albart' GoLemM.

Nov. 18, 1941. A. COLEMAN 3 3 PHOTOGRAPHIC MACHINE Filed June 15, 1939 3Sheets-Sheet 2 Fig. 3

Inuentor,

Abborhel Nov. 18, 1941. A. COLEMAN 2,263,380

PHOTOGRAPBIC MACHINE Filed June 15, 1939 v 3 Sheets-Sheet 3 Inuetor.

Patented Nov. 18, 1941 UNITED STATES PATENT 'OFFICE Application June 15,1939, Serial No. 279291 In Great Britain May 15, 1939 s Claims.

Photographic machines delivering pictures in a few minutes are known toconvey the sensitized sheets of paper, film or other material to thebaths and from one bath to the other up to final delivery,automatically.

For the purpose of 'such transport various systems are in use, utilisingeither chains, rollers, ribbons and hooks or a combination of them, butall imparting to the sheets a movement that subjects them to effortsfrom sliding, pushing, pulling or rubbing on the various parts of thebaths with which they come into contact.

The present invention realises a method by means of which the sheets ofsensitized material are transported, while in the baths, by a mechanicalsystem which allows them to remain immobile while thus transported andexcludes,jn suppressing all pushing, pulling or sliding of the sheets,the-possibility of their rubbing, Scratching and crushing as they arenot allowed to come into contact with any parts of the baths whatsoever.

According to this invention the sheets of sensitized material while inthe baths are held between the inner borders of two endless steelribbons which leave the sheet entirely exposed to the bath. Theseribbons traverse the bath into contact with each other; only saidribbons receive all strains and rubbing from the tank members of thebath.

The steel ribbons are stretched by means of rollers and maintained on acurved path between said rollers by means of suitable convex surfaces onwhich they slide, so that their clamping action is maintained.

The rollers are not carried directly by the bath tank but are Secured toa frame which is immersed into the bath. Each sheet in each bath istaken in between the ribbons, passes downwards and upwards and is thenreleased. A continuous movement is imparted to the belts by a drivingroller mounted at the upper part of the driving mechanism and having itshorizontal spindle rotatably supported by the frame of the apparatus.The tank of the apparatus is raised and hung to the frame instead oflowering the frame into the bath, thus facilitating maintenance andcontrol of the conveyor.

The driving roller is removably Secured to its rotating spindle, so thateach tank and its conveyor may easily be removed from its spindleindependently of the remaining tanks.

The annexed drawings show an embodiment of this invention.

Fig. 1 shows diagrammatically the conveyor with endless ribbonsaccording to this invention.

Fig. 2 shows the particular form of the endless steel ribbons. I

Figs. 3 and 4 are cross and longitudinal section respectively,relatively to the driving axis of a bath for sensitized material of anautomatic or semi-automatic camera.

As shown in Fig. 1, two endless ribbons a, b are stretched each betweenapair of parallel rollers c, d and touch each other at their inner edgesa' and b'; the sheet introduced between said edges is carried throughthe bath.

The contact between the edges a' and b' is ensured by the fact that oneof the ribbons slides on a convex surface c', the other ribbon, beingstretched between its rollers, is forced to adhereto and take the exactcurvature of the former. The ribbons are of wide U-shaped section (Fig.2) the U branches of the two ribbons are face to face and between themthe sheets s is gripped along two edges. In the U web are formed largeopenings, so that the ribbon is constituted by two continuous marginalbands m and n connected together by a plurality of cross members r withturned-in ends for connection to the bands. The ribbon maintains thusthe necessary flexibility to adapt itself to the curvature of rollers ofsmall diameter while the liquid (or gas) of the bath may circulatefreely on both surfaces of the sheet s.

The conveyor (Figs. 3 and 4) comprises two plates l connected and spacedapart by means of an upper crosspiece la and lower crosspiece lb. Bothplates are of elongated form and arranged vertically in the apparatus;they are hung to the spindle 3 fixed to a crosspiece 4 of the apparatusframe by means of a sleeve 2 Secured to the rear plate. The plates carrya tank 5 by means of two hooks 6 engaging lugs 1 of the tank; the tankmay thus be easily removed without taking away the conveyor from thecrosspiece 4. The plates carry at their upper part a cover 8 Secured bymeans of screws; resilient blades 9 act as spacers between the tank andplates.

The bath tanks 5 (Fig. 3) are placed adjacent to each other but for anarrow gap' due to the presence of blades III (Fig. 3) ensuring thevertical position of the tanks and carried by the frame of theapparatus.

The conveyor is constituted by a driving and a driven ribbon. Thedriving ribbon Il is stretched (Fig. 3) between a large upper drivingroller IZ, rotatable on a sleeve 2 and a small lower roller !3 rotatablewithin bushings of a !ork N (Fig. 4), the stem IS of which slidestelescopically, under the action of a spring li. within a tubularsupport I'I carried by the crosspiece lb; the driving ribbon, whenreleased from or returned to the upper roller l2, passes over therollers of smaller diameter i& that deflect it towards the central planeof the rollers l2-l 3. The driving ribbon H between the lower roller 3and rollers s slides both on the upward and downward branch on convexblades i! secured to the plates I and provided with wide openings (notshown in Fig. 4).

The driven ribbon 20 forms two interlinked v's, the outer one beingcomprised between the upper rollers s and lower roller 2| of largediameter and the inner one between said rollers i! and the roller l3;the driven ribbon is superposed on the driving ribbon on the lengthbetween the rollers I& and roller 2l; both ribbons are maintained in thestretched condition by a spring IS once the exact initial tension has,been adjusted. The side walls of the cap 8 are provided with twohorizontal slots in planes nearly tangential to the rollers s; in saidslots are fltted sheet guides 22, through one oi' which is passedthe-sheet to be treated in the bath 5. said sheet, gripped by theribbons II and 20, as shown in Fig. 1, is first carried downwards andthen upwards and passed to the next sheet-guide. The sheet does notundergo any stress in the bath and does not come into contact with anypart of the tank. The outlet slot from a bath registers with the inletslot in the next bath, so that the sheet passes automatically from oneto the next bath; obviously the ribbons in the various baths move at thesame speed, the driving rollers |2 being positively connected to eachother.

The driving roller |2 is actuated by a shaft 23 freely rotatable withinthe supporting spindle 3, which is provided at its end with a prismaticboss zaa carrying a flywheel 24, fixed by a. nut or resilient stop; theshaft is connected to the roller by means of radial pins 24' extendingfrom the roller and engaging axial notches in the flywheel. Removal ofthe fiywheel 24 stops the conveyor, which is very advantageous for thecontrol of the machine.

The bath is provided with a. stirring device constituted by a doublescrew 25 carried by a sleeve l'l of the crosspiece and set into rotationby a roller [3, which is suitably constituted by two sections keyed on ashaft l3a, by means of a pair of bevel gears 26, a Vertical shaft 21 andanother pair of bevel gears. The shaft 21 is made of two sectionsconnected together by a joint allowing the shaft to adapt itself to thedeformations of the spring IS. The tank 5 is provided with a filler 28,an overfiow pipe 29 and a bottom plug 30.

The constructional details of the conveyor, tank and driving mechanismmay of course be modified according to practical requirements.

What I 'claim is:

1. Conveyor for sheets to be passed through treatment baths, comprisingtwo endless ribbons of U-section, the flanged ends of the branches ofthe ribbons being into contact with each other during part of the travelof said ribbons and the web of said ribbons being provided with largeopenings, means for Operating one of said ribbons, the other beingcarried into motion by friction with the former, the sheet being grippedalong its side edges between said branches, transported through the bathand released at the end of its travel through the bath.

2. Conveyor for sheets to be passed through treatment baths comprising adriving roller. a driven loose roller, an endless driving ribbon passingover said rollers, two guiding rollers arranged in proximity to thedriving roller on each side of said driving ribbon, a floatingstretching roller under the driven roller, an endless driven a ribbonpassing over the driven roller, both guiding rollers and tensioningroller in such inanner as to form two V's one inside the other, theportion of the driven ribbon !orming the inner V beinginto contact withthe driving ribbon. convex guiding surfaces for the contacting lengthsoi' the ribbons, a passageway for the sheets to permit their insertionbetween the two ribbons, said passageway being arranged between thedriving roller and one of the guiding rollers and means arranged betweenthe driving roller asrd t;the other guiding roller for releasing the 3.Conveyor, as claimed in claim 2, in which the endless driving ribbon andthe endless driven ribbon are of U-section, the flanged ends oi thebranches of said two ribbons being into contact with each other alongthe portions between the driven roller and the guidingrollers, the webof said ribbons being provided with large openings extending from one tothe other branch.

4. Conveyor, as claimed in claim 2, comprising a resilient stretohingdevice for supporting the driven roller and maintaining both endlessribbons in the stretched condition.

'5. Conveyor i'or sheets to be passed through treatment baths,comprising a driving roller, a

hollow fixed spindle, on which said roller is roi tatably mounted, adriving shaft passing through said spindle, means for coupling in aneasily removable manner said shaft 'with said roller withoutdiscontinuing the rotation or the driving shaft, a driven roller, anendless driving ribbon passing over said rollers, two guiding rollersarranged in proximity to the driving roller on each side of said drivingribbon, a floating stretching roller under the driven roller, anendlessdriven ribbon passing over the driven roller, both guiding rollers andthe tensioning roller in such manner as to form two V's one inside theother, the portion oi' the driven ribbon forming the inner v being intocontact with the driving ribbon, convex guiding surfaces for theContacting lengths of the ribbons, a passageway for the sheets to permittheir insertion between the two ribbons, said passageway being arrangedbetween the driving roller and one of the guiding rollers and meansarranged between the driving roller 'and the other guiding roller forreleasing the sheet.

6. Conveyor for sheets to be passed through treatment baths, comprisinga driving roller, a hollow fixed spindle, on which said roller isrotatably mounted, a driving shaft passing through said spindle, meansfor coupling in an easily removable manner said shaft with said rollerwithout discontinuing the rotation of the driving shaft, a drivenroller, an endless driving ribbon passing over said rollers, two guidingrollers arranged in proximity to the driving roller on each side of saiddriving ribbon, a floating stretching roller under the driven roller, anendless driven ribbon passing over the driven roller, both guidingrollers and the tensioning roller in such manner as to form two V's oneinside the other, the portion of the driven ribbon forming the inner Vbeing into contact with the driving ribbon, convex guiding surfaces forthe contaeting lengths of the ribbons, supporting piates for saidrollers supported by said fixed spindle, convex guiding surraces for thecontacting portions o! the ribbons, said surfaces being supported bysaid plates, a guiding channel for the sheets to permit their insertionbetween two ribbons on one side of the conveyor and a guiding channeltor'receiving the sheet issuing from the bath.

7. conveyor as claimed in claim 6, comprising a stirring device arrangedbetween said convex guiding surtaces and a transnitting device adaptedto transmit the motion rrom said driven roller to said stirring device.

8. A device for conveying sheets through a 15 5 ranged between saidflanged ends being provided with large openings, means ior .positlvelydriving one of said belts. while the second belt is driven by Irictionalcontact with said first. driven belt, said belts gripping said sheets attheir edges 10 while leaving practically the entire surface of saidsheets free to the access of the bath, said conveyor belts transportingthe sheets through the bath and releasing the sheets at the end of theirtravel through the bath.

ALBERT COLEMAN.

